1. Field of the Invention.
This invention relates generally to a computer graphics system, and more particularly, to a method for converting Non-Zero Winding fill polygons to Even-Odd fill rule polygons.
2. Description of Related Art.
In the field of computer graphics, Non-Zero Winding and Even-Odd are two common fill rules used to determine whether a region of a polygon is inside or outside. These two methods each enable distinct descriptions of polygons. However, they pose an extra burden in creating generic computer algorithms for polygons. No exchange method exists for converting one rule to the other. Therefore, a computer program designer has to expand his logic to accommodate both cases. This logic expansion complicates the design and at times may prevent reuse of computer programs.
Thus, there is a need in the art for an invention that converts Non-Zero Winding fill polygons to Even-Odd fill polygons. Additionally, the invention should remove any inside edges of a Non-Zero Winding rule polygon. This means that the output of the invention only consists of the actual border or outside edges of a polygon. Redundant points are removed.